Biophysics

266) Which element of the eye’s optic system shows the highest optic power (measured in Dioptres):

267) If the curvature radii of the lens increases 2 fold, then the optic power (measured in dioptres) of the lens:

268) Accommodation of the eye is related to:

269) mechanism of accommodation is related to the properties of

270) When the action potential reaches its maximal (peak) value, the membrane potential reaches approximately:

271) When the action potential reaches its minimal value (hyperpolarization), the neuronal membrane is

273)   The acetylcholine receptors at the end plate in the muscle fiber are

274)   Decrease in potassium ion concentration in the extracellular fluids would cause:

275) Entropy is a measure of :

277)  When the function of the f channels in the SA node is increased:

278)  The first principle of thermodynamics for ideal gas states that the change of internal energy of a closed system is equal to

279)  Indicate where are localized hirachial pacemakers in the heart

280) The sample contains 2000 atoms of radioactive isotope whose half-life is 50 years. Radioactive decays will reduce the initial number of radioactive atoms to 125 after:

281)  Radiation-induced ionization of gas occurs in:

282)  Van der Waals attractive interactions are due to:

286)  Which mode(s) of ultrasonography provides a direct information about the amplitude of echoes:

287) After the light absorption by a photoreceptor the membrane potential is:

288) The force of electrostatic interaction between two electric charges is

289) The energy of interaction between two dipoles is:

290) Van der Waals attractive interactions are due to

292) The sample contains 2000 atoms of radioactive isotope whose half-life is 50 years. Radioactive decays will reduce the initial number of radioactive atoms to 125 after:

293) During MRI scan a patient is placed in the constant magnetic field of a scanner and the protons in patient’s body absorb pulses of electromagnetic radiation whose frequency is typical for:

294) In ultrasonography reflections of ultrasound waves (echos) may occur at the boundary between two tissues:

295) The underwater rock is 6 km from a submarine. What is the time (starting from sound emission) of echo return to the sonar if the speed of sound in water is 1500 m/s?

296) The NMR phenomenon is related to:

297) The mean kinetic energy of particles in an ideal gas is:

298) The intensity of the electrical field (E = U/d, U – voltage, d – distance) within the biological membrane is close to:

299) The phenomenon of viscosity is related to:

300) Viscous resistance (haemodynamic resistance) is defined as:

301) After action potential generation in the axon:

302) Which element of the eye’s optic system shows the highest optic power (measured in Dioptres):

303) If the curvature radii of the lens increases 2 fold, then the optic power (measured in dioptres) of the lens:

304) Accommodation of the eye is related to:

305) mechanism of accommodation is related to the properties of

306) When the action potential reaches its maximal (peak) value, the membrane potential reaches approximately:

307) When the action potential reaches its minimal value (hyperpolarization), the neuronal membrane is

308) Electrical capacitance of a membrane:

309)   The acetylcholine receptors at the end plate in the muscle fiber are:

310)   Decrease in potassium ion concentration in the extracellular fluids would cause:

312)  The physical properties of the medium changed and the density (p) increased twice and sound velocity (c) increased fourfold. Indicate how much the acoustic impedance has changed